Separable attachment plug



Feb. 19, 192%; 1 484A94 w. H. HARRINGTON SEPARABLE ATTACHMENT PLUG Filed Dec. 30. 1922 HAS A TTOH/VEYS Patented Feb. is, neat.

Nil

' Mttddtld WILLIAM H. RINGTOIN', OF HARTFORD, CONNECTICUT, ASSIGNOE TO THE ARROW ELECTRIC COMPANY, OF HARTFORD, NECTICUT.

CONNECTICUT, A CURPDEATION 0F CON- SEPAR LE ATTACHMENT PLUG.

Application filed December 30, 1922. Serial Flo. 602,852.

To all whom it may concern:

Be it known that I, WILLIAM H.115 RINGTON', a citizenof the United States of America, residing at Hartford, in the county tion being to provide a strong and simple construction which can be manufactured economically with the minimum number of operations and with the minimum number of parts.

In the accompanying drawings Fig. 1 is a vertical section through the plug base and cap. separated from each other; S

Fig. 2 is a perspective view of the ele- .ments of the base ortion disassembled;

Fig. 3 is a vertical section of a modified form of base; and

Fig.4 is a horizontal section on line 44 of Flg. 1.

The plug as usual is composed of a cap member 5 and a base member 6. Contact blades 7 are fastened to the cap 5 by hollow rivets or otherwise, and binding posts 9 for the. wires are mounted on integral extensions of the bases of the blades 7.

The base portion 6 has an insulating bod 10 with parallel slots 11, 12 passing throng 1 the body in a longitudinal direction. These slots are spaced to receive the contact blades 7 of the cap.

Spring contacts 13 and 14 located in these slots 11 and 12 respectively are adapted to engage the blades 7 when the cap is put on the base. These spring contacts are made of fiat metal strips substantially the width of the slots 11 and 12. On the lower end of the base is a cup-shaped screw shell member 15. The bottom of this cup-shaped member lies over the end of the base and is punched out as. shown in Fig. 2. This stamping produces a flange with an openmg leaving a generous-clearance for slot 11 but with a notch 16 just the width of slot 12 partially overlying the latter slot. (See Fig. 4.) This leaves just a narrow slit open over slot 12. The end of spring contact 14 is passed through this narrow slit and bent over on the outside of the bottom flange of the screw shell. With the spring contact 14 fitting snugly between the side walls of both the slot 12 and the notch 16, it is lmpossible for the screw shell to rotate on the insulating body. This method of holding the screw shell from rotation is simple and efiective, requiring no fastenings of any kind.

The flange of the screw shell, the insulating body and the end of the spring contact 14; are covered and clamped in place by an insulating button 17. This button is recessed at 18 to seat the end of the spring contact 14 and permit the button to press flush against the screw shell also. The spring contact 13 passes through a slot 19 in the button and is bent down over the center of the button to form a connection with the center contact. The means for holding the various parts together may be of any suitable kind. In Figs. 1 and 2 ll show a tubular rivet 20 imbedded in the insulating body passing through the insulating button and spun over the end of the spring contact 13 thus assembling the parts firmly together in one operation, and at the same time forming the center contact. An-

other means for fastening the parts together is shown in Fig. 3. In this construction a bolt and nut operating against a shoulder 21 in an axial bore 22 take the place of the tubular rivet of Figs. 1 and 2.

It will beg parent that my form of base canbe asse led in one simple operation and that it is a strong construction affording good electrical contacts between the parts in the electrical circuit. The tighter the plug is screwed into a socket the tighter are the parts of the electrical contacts in the plugQpressed. together. It should be noted alsothat all the strains incident to unscrewing the plug fall directly on the insulatin body.

What claim is 1. A separable attachment p111 base having an insulating body, a screws ell fitting over one end thereof, and a slotted insulating button on said end and said screw shell, in combination with two contacts in said body projecting through said screw shell, one of said contacts forming electrical contact with the screw shell an latter from rotating on said body.

preventing the 2. A. separable attachment plug base hav- 7 Y ing an insulating body, a screw shell fitting over one end thereof and having a notched opening in the bottom thereof, and a slotted insulating button on said end and said screw shell, in combination with two contacts in said body projecting through the notched opening in the bottom of said screw shell, one of said contacts engaging the notched opening of said screw shell and preventing the latter from rotating on said body.

3. A separable attachment-plug base having an insulating body with slots, and a screw shell fitting over one end thereof, in

combination with an end insulating button,

means uniting said insulating body and but- 15 ton, and contact springs in said slots, one of said springs having its end clamped between a flange on the screw shell and the insulating button, and the other having its end clamped on the outside of said button 20 WILLIAM H. HARRINGTON. 

